Circuit-breaker.



M. P RYDER. CIRCUIT BBELKER, APPLICATION FILED APB-19. 1904.

998,990, Y Patented July 25, 1911.

w/nmses:

INVENTO/Z A BY MALCOLM LP. RYDER, 01? WHITE PLAINS, NEW YORK.

GIBCUIT-BREAKER.

Specification of Letters Patent.

Patented July 25, 191.3.

Application filed April 9, 1904. Serial No. 202,287.

To all whom it may concern:

Be it known that I, MALCOLM P. RYDER, a citizen of the United States,and a resident of White Plains, in the county of lVestchester and Stateof New York, have invented a new and Improved Circuit-Breaker,

, of which the following is a full, clear, and

exact description.

My invention relates to circuit breakers, and admits of general use, butis peculiarly applicable in cases where it may be desirable to break thecircuit only when there is a long continued excess of current flowingthrough it. In other words, I seek to .produce a type of circuit breakerwhich is sensitive to long continued excesses of current, but which isnot affected by momentary increases or decreases of the same.

My invention consists in the novel-disposition or relative arrangementof a transformer, a fuse and coils for a magnetic circuit breaker whichcontrols the circuit of the primary of the transformer, such noveldisposition or arrangement comprising magnetic circuit breaker coils andthe fuse in shunt relation to one another upon the secondary circuit ofthe transformer, as is hereinafter described and then specified in theclaims.

By my invention, as Will be hereinafter more apparent, l secure not onlyreliability of action, but provide a Wide margin of ad justineut andoperation for the circuit breaker and further simplify and reduce thesize of the device and secure freedom from danger in operation of theapparatus.

' Reference to be had to the accompanying drawings forming a part-oil.his specification, in which sim lar characters of reference indicatecorresponding parts in all the figures. I a

Figure 1 is a side elevation, partly diagrammatic, showing my inventionin use; and Fig. 2- is a section upon the line 2--2 of Fig. 1, lookingin the direction indicated by the arrow.

Upon the board 1 is mounted a post 2, pivoted upon which is a knife 3,engaging a bifurcated contact the post 2 and the contact a beingprovided respectively with terminals 5, 6, all of these partsconstituting a soealled knife switch. From the terminal 5 a wire 7 leadsto the dynamo 8, and

Fig. 2.

from this dynamo a wire 9 leads to the pri mary winding 10 of atransformer 11. The secondary winding of this transformer is connectedwith the wires 13, 14, for energiz ing the lamps 15, which are connectedin the usual or any desired manner. From the primary winding 10 a. wire16 leads to a primary winding 17, from which a. wire 18 leads to theterminal 6. The secondary winding 19 is disposed adjacent to the primarywinding 17, these two windings coustituting a. second transformer. Afuse 20 provided with terminals 21, 22, is connected to a circuit 46,4-7 and in shunt relation to a magnet coil 38 on said circuit as shown.The upper end of the knife 3 provided with a head 23, connected theretoby the insulation 2%. Journaled upon this head is a link 25, which ispivotally connected with a sliding rod 26, passing through a cap 27,this cap being rigidly mounted upon a board 32. One end of this cap 27is provided with a plate 28, and resting against this plate is a spiralspring 29, which also engages an annular boss 30, mounted rigidly uponthe sliding rod 26. r inother spiral spring 31 is mounted upon theopposite side of the annular boss 30, and serves as a buffer to cushionthe movements of the sliding rod 26 in one of its longitudinaldirections, as will be seen from Fig. 1. A post 38 is rigidly mountedupon the board 32, and ournalcd upon this post is a knife 34, providedwith a. handle 3:) and with a slot 36, this slot being loosely engagedby a sliding pivot 37, rigidly mounted within the sliding rod 26. A.solenoid 38 is provided with a movable core 39, the upper portion 4-0 ofwhich is comparatively small and is rounded upon its upper end as shown.The sliding rod 26 is provided with a notch 4C1, as shown moreparticularly in A sleeve 42 is loosely mounted upon a stationary boss49, being held in position by the disk 4.3, this disk being secured by apin passing diametrically through the boss 49, as indicated in dottedlines in Fig. 2. The boss 49 is rigidly mounted upon a base or bracketwhich is in turn rigidly connected with the board said boss carrying anarm 4%, normally engaging a notch 2-1 as shown in Fig. 2. Wires 46, 4.7,connect the transformer 19 and the fuse 20 with the solenoid 38, thearrangen'ient of these memhers being preferably such that the fuse 2O 11ondary winding 19, and slightly elevates the or equivalent magnetic andsolenoid 38, member of the circuit breaker, are connected in parallelwith each other across the secon ary circuit. Owing to the impedance ofthe coil in shunt relation to the fuse but little current flows in theshunt around the fuse while same is intact, but when the fuse blowsopening the short circuit path, the current is forced to act on themagnetic member of the circuit breaker. A bracket -it8 normally supportsthe core 39 in its lowermost position.

The action of my device as follows The dynamo 8 being started up, theprimary windings 10 and 17 are energized, and they in turn actinductively upon the secondary windings 12 and 19. The fuse 20 is ofsuch thickness as to be rendered insensitive to momentary increases incurrent, but is readily melted by an excess of current if the same belong continued. As will be seen, the fuse forms a shunt of low orpractically no inductance around the solenoid coils of the magneticcircuit breaker,'while, on theother hand, the coils themselves being ofcomparatively high inductance, there is an eX- tremely effectualshunting of the alternating currents around said coils so long as thefuse remains intact. Hence, so long as the alternating current on thesecondary is insufficient to melt the fuse, practically no current willflow in the coils of the magnetic circuit breaker and the current flowon the main circuit and on the secondary may vary within very widelimits without affecting to any appreciable extent the strength of thesolenoid. his insures complete freedom from accidental operation of thedevice under ordinary variations of load on the main circuit of thesystem and gives, in effect, a wide margin of action or adjustment forthe magnetic circuit breaker. hen, however, an overload occurssuflicient to melt the fuse, then all the current theretofore divertedfrom the coils by the cooperation of the low inductance in the fusebranch and the high inductance in the coil branch of the ondary iscompelled to flow in said coil, and

the circuit breaker will be caused to act as hereinafter more fully setforth. The usual position of the apparatus, while the dynamo 8 is inaction, is shown in Fig. l, the knife switches 3 and 354. being in theposition indicated Alternating currents are sent through the prin'iarywinding 17, and these in turn induce alternating currents in thesecondary winding if), thereby throwing more or less current.through thefuse 20, which thus serves to short; circuit the solenoid 38, so as torender the same inactive. A. momentary increase of current through theinain circuit of course roduccs a momentary increase of current throughthe sectempe *ature of the fuse 20. If the excess of current is onlymomentary, however, and not of too great n'iagnitude, the fuse 20 is notmelted, and therefore continues to serve as a short circuit for themagnetic member 38. it, however, the excess of current be longcontinued, the fuse 2t) melts out and. the entire current. of the localcircuit passes through the wires 46, 4:7, and solenoid 38, which nowoperates as a trip coil for the automatic circuit breaker and beingabruptly energized lifts the core 39. The upper portion 40 of this corethereupon raises the arm 4:45 out of the notch {L1, and thereby releasesthe sliding rod 236. This rod acting under tension of the spiral spring29 suddenly moves to the right, thereby moving the knife so as to openthe switch and stop all flow of current in the main circuit.

I am aware that circuit breakers have heretofore been used in which anexcess of current.- in a main or working circuit caused a fuse in saidcircuit to blow and thus open the circuit. Such circuit breakers,however, cannot be depended upon to safely and surely open a circuitcarrying a large amount of power at high voltage. In my device the fuseis traversed by current. of small volume and voltage as compared withthat on the main circuit or circuit to be protected and is not dependedupon to .open said main or other circuit directly but merely brings intoaction at the proper time the n'iagneticmeinber of an autoi'i'iaticswitch or circuit breaker, which member is in shunt relation to the fusein a circuit. inductively related to the main circuit and opera tes torelease the circuit breaking member of the autoi'natic circuil breakeror switch.

M y invention C(Hl'lbll'lCS the safety and reliability of the.aulxmiaticswitch for opening the circuit and the time limit of the fuse. 1 do notlimit; myself, however, to the particular arrangcn'ient of the mechanismabove described, nor to the electrical connections dis- 110 closcd,""for obviously these details may be varied considerably withoutdeparting from the spirit of my invention.

Having thus described my invention, I claim as new and desire to secureby Letters lat en t 1. The combination, substantially as do scribed, ofa transformer, 21 n'iaguctic circuit breaker for the main circuit of thesystem, a fuse and magnetic coils for said circuit breaker in shunt orparallel relation to one another on the secondary of the transformer, asand for the purpose set forth.

The combination of a main or working circuit. an automatic circuit;ln'cakcr for inlorrupting the How of excess current thcrcin, atransformer connected to said circuit, a fuse and trip coils for saidcircuit breaker,

said fuse and coils being in shunt or parallel relation to one anotheron a secondary of the transformer forming, respectively, low inductanceand comparatively high inductance branches fclr the flow of thealternating currents furnished from the secondary.

In testimony whereof I have signed my name to this specification in thepresence'of two subscribing Witnesses.

MALCOLM P. RYDER.

Witnesses:

WALTON HARRISON, EVERARD BOLTON MARSHALL.

